- Hydroxychloroquine is a drug used to treat malaria and lupus
- It has antiviral properties against the 2003 coronavirus SARS
- There are very few trials involving these drugs and COVID-19
Since the end of March, President Donald Trump has been touting the use of hydroxychloroquine to help tamper down the threat and to treat the effects of COVID-19. In fact, he tweeted that the drug could be “one of the biggest game-changers in the history of medicine.”
Here’s what is known about the possible effects on the novel coronavirus by hydroxychloroquine, which is a “less toxic derivative” of the drug chloroquine.
Claims of the drug’s efficacy against coronavirus rely on its anti-inflammatory properties which are present when used to treat malaria—a disease caused by a parasite, not a virus—and the 2003 coronavirus SARS epidemic. Because the drug was effective in treating a previous form of coronavirus, specialists have posited that it may be worth a shot for the treatment of the new coronavirus.
In a letter to Nature magazine, researchers from the Wuhan Institute of Virology and Chinese National Virus Resource Center wrote that a new antiviral drug remdesivir and chloroquine may both be effective in treating the 2019 coronavirus. Specifically, they blocked the infection of healthy cells, making the drugs an effective preventative measure. The drug’s anti-inflammatory components also would help treat COVID-19.
Chloroquine works by increasing the pH of the cell, making cell-virus fusion difficult if not impossible. Even if coronavirus entered the lung, it would be unable to bind with any healthy cells or reproduce.
Trials of the drug as treatment for previous versions of the virus in mice have shown to be “highly effective.” This makes the case that chloroquine potentially could be both a suitable preventative measure and a treatment for the virus.
However, it is worth noting that very little is known about how this drug may interact with the novel coronavirus in vivo, or in the human body, and is based almost entirely off of interactions with previous strains.
On April 17, the Los Angeles Times reported that researchers in China, France, and Brazil determined that chloroquine and hydroxycholorquine “largely failed to deliver improvements” on some “key measures” of the coronavirus and in two cases might have caused heart troubles among a few patients. In France, the drugs didn’t reduce deaths, and in separate studies in China and Brazil, they didn’t help patients recover from the virus any faster. In Brazil, the researchers have stopped using those drugs on patients.
“Preliminary findings suggest that the higher chloroquine dosage should not be recommended for COVID-19 treatment because of its potential safety hazards,” the study authors wrote.
On April 21, the Associated Press reported that among 368 patients in U.S. veterans hospitals, more infected victims died when giving hydroxychloroquine than those who received standard care. About 28% of those infected who were given the drug died. For those who did not receive hydroxychloroquine, 11% died.
On May 18, Trump said he had been taking hydroxychloroquine for more than a week. “So far,” he told reporters, “I seem to be OK.”
In a study released a few days later, it was reported that an analysis of 96,000 patients that had been given hydroxychloroquine showed they were much more likely to die and develop heart issues. “It’s one thing not to have benefit, but this shows distinct harm,” Eric Topol, a cardiologist and director of the Scripps Research Translational Institute, told the Washington Post. “If there was ever hope for this drug, this is the death of it.”
On May 26, the WHO said it was halting its trial with the drug, citing the study that said it had dangerous side effects.
On July 29, despite Donald Trump’s hydroxychloroquine recommendations continuing, the state of Ohio said pharmacists can’t prescribe hydroxychloroquine for coronavirus patients.